The invention relates generally to refrigeration systems used to cool or heat a confined space and, more specifically, to bulkheads used to direct cooled or heated air in a confined space on a vehicle capable of transporting goods.
Air return bulkheads of the type described herein provide a flow path for air through a climate-controlled space within a vehicle, while simultaneously protecting the refrigeration equipment from damage. The air from within the controlled space of the vehicle enters the bulkhead through an inlet and travels to the refrigeration system where it is heated or cooled before returning to the controlled space.
Dirt and debris that collects on the floor can be pulled into the bulkhead and can contaminate the refrigeration system. Dirt and debris entering the refrigeration system can lodge within the evaporator, eventually reducing the air flow substantially. Some systems will interpret the blockage as ice and will cycle the refrigeration system into defrost mode, which is ineffective at removing the debris. The system will therefore operate inefficiently until it is cleaned manually, or it will continuously cycle into defrost mode until an alarm is generated and the system shuts down.
The air return bulkhead of the present invention includes a plurality of walls defining a climate-controlled space such as a truck trailer. A refrigeration system supplies cold or heated refrigerant to an evaporator. The evaporator has a refrigerant flow path for refrigerant and an air flow path for air from the climate-controlled space. The evaporator thus uses refrigerant to cool or heat air, and the air then flows back into the climate-controlled space to heat or cool the goods therein.
The air return bulkhead is attached to one of the walls defining the climate-controlled space, substantially covering the inlet of the evaporator airflow path. The bulkhead has a hinged cover that allows easy access to a filter located within the bulkhead. In addition, the bulkhead has an air inlet and an air exhaust. When the refrigeration system is operating, air from the climate-controlled space is pulled into the air return bulkhead air inlet, passes through the filter, and then enters the evaporator air flow path. After being cooled by the evaporator, the air exits the system through the air exhaust and reenters the climate-controlled space.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims, and drawings.